The JAK1/2 inhibitor ruxolitinib downregulates the immune checkpoint protein B7H3 in multiple myeloma

Hematol Oncol. 2023 Aug;41(3):578-582. doi: 10.1002/hon.3071. Epub 2022 Sep 5.

Abstract

We hypothesized that ruxolitinib may inhibit the immune checkpoint protein, B7H3; and, thus, investigated its effects on this immune inhibitor using multiple myeloma (MM) cell lines, bone marrow (BM) mononuclear cells from MM patients and human MM LAGλ -1A xenografts. Ruxolitinib reduced B7H3 gene and protein expression and increased IL-2 and CD8 gene expression. These results suggest that ruxolitinib inhibition of B7H3 may restore exhausted T-cell activity in the MM BM tumor microenvironment.

Keywords: B7H3; Janus kinase inhibitor; multiple myeloma; tumor microenvironment.

Publication types

  • Letter

MeSH terms

  • Humans
  • Immune Checkpoint Proteins / pharmacology
  • Janus Kinase 1
  • Multiple Myeloma* / pathology
  • Signal Transduction
  • Tumor Microenvironment

Substances

  • ruxolitinib
  • Immune Checkpoint Proteins
  • Janus Kinase 1
  • JAK1 protein, human